Microsoft is moving full steam ahead toward delivering most of its new SQL Server 2008 R2 versions to customer by May. But its high-end SQL Server 2008 R2 Parallel Data Warehouse isn't going to be out in the first half of this year, as the company originally anticipated.

On April 2, Microsoft officials said that the R2 Parallel Data Warehouse -- codenamed "Madison" and based on the DATAllegro technology Microsoft purchased in 2008 -- has no public due date. Microsoft is shipping a final technology preview of that product to private testers today and is seeking more Technology Adoption Program (TAP) participants interested in the data warehouse SKU, officials said via a blog post.

"Although our intent was to deliver SQL Server 2008 R2 Parallel Data Warehouse in the first half of 2010, we are still gathering customer feedback and working to ensure the high quality release our customers expect. Based on feedback from the customer Technology Adoption Program, we expect to announce more specific release timing, final configurations and pricing for our hardware partners in early summer (northern hemisphere). Stay tuned!" according to the SQL Server Team blog post.

The Parallel Data Warehouse version of SQL Server 2008 R2 will be sold preloaded on servers as a data warehouse appliance. Using the DataAllegro technology Microsoft acquired in 2008, it will scale customers’ data warehouses from the tens of terabytes, up to one petabyte plus range, according to the company.